Two-stage timer mechanism



Aug. 9, 1966 A. L. DILPARE 3,254,948

TWOSTAGE TIMER MECHANISM Filed April 2, 1963 68 Pafidus Pie/6 United States Patent 3,264,948 TWU-STAGE TIMER MECHANISM Armand L. Dilpare, Hicksville, N.Y., assignor to Lundy Electronics and Systems, Inc, Glen Head, N-Y. Filed Apr. 2, 1963, Ser. No. 270,004 1 Claim. (6]. 91-411) This invention relates generally to the field of pneumatic timers of a type in which movement of a resiliently urged element is controlled through the escaping flow of a fiuid under compression from contact with said resiliently urged element.

In many automated devices, it is often necessary to initiate two separate operations, the second of which must take place a predetermined short interval of time after the first. While it is possible to employ two separate singlestage timers of the above-described type, in which one operates at a slower rate than the other, both single timers being simultaneously actuated, because there is no interrelation between the operation of the two timers, the desired serial function is difiicult, if not impossible, to obtain.

It is therefore among the principal objects of the present invention to provide an improved two-stage pneumatic timer mechanism in which the initiation of operation of the first-stage component thereof is externally controlled and the initiation of operation of the second-stage element is controlled by the first-stage element.

Another object of the invention lies in the provision of a two-stage pneumatic timer mechanism which may be of relatively small over-all dimensions, and of correspondingly low weight, whereby the same may have a wide utility in various types of installations.

Still another object of the invention lies in the provision of an improved two-stage pneumatic timer mechanism which may be of suificiently low cost of manufacture as to be expendable after a single cycle of operation, and which nonetheless may be of such simple construction as to be incapable of malfunction.

A further object of the invention lies in the provision of an improved two-stage pneumatic timer in which substantially all of the operative parts are disposed Within a casing element, to be shielded from accidental damage or misadjustment.

A still further object of the invention lies in the provision of an improved two-stage pneumatic timer mechanism wherein each timing stage is adjustable before use, over a wide range, by simple adjustment of the force in the incorporated resilient members.

A feature of the invention lies in the fact that although employing relatively small resilient forces, the disclosed embodiment is capable of controlling the application of much greater forces.

Another feature of the invention lies in the fact that the device, if desired, may be pressurized at the time of manufacture, requiring no subsequent pressurizing before use.

Still another feature of the invention lies in the fact that the device, if properly proportioned, will function so that there is no mechanical motion (except for escaping flow of fluid) during the major portion of each timing interval.

These objects and features, as well as other incidental ends and advantages, will more fully appear in the progress of the following disclosure, and be pointed out in the appended claim.

In the drawing, to which reference will be made in the specification, similar reference characters have been employed to designate corresponding parts throughout the several views.

FIGURE 1 is a plan view of an embodiment of the invention.

Patented August 9, 1966 "ice FIGURE 2 is a longitudinal central sectional view thereof, as seen from the plane 22 in FIGURE 1.

FIGURE 3 is a plan view showing a first phase of release of one of the latch elements forming a part of the embodiment.

FIGURE 4 is a similar plan view, showing a subsequent stage.

FIGURE 5 is an amplified view of the encircled portion of FIGURE 2.

In accordance with the invention, the device, generally indicated by reference character 10, comprises broadly: a casing element 11, a first-stage timing element 12, a second-stage timing element 13, a first-stage latch element 14, and a second-stage latch element 15.

The casing element 11 may be formed of any suitable material, but is preferably formed as a precision die cast ing. It includes an outer cylindrical wall 18, first and second end Walls 19 and 20, and a generally centrally disposed dividing wall or septum 21.

The outer cylindrical wall 18 includes a recess 22 disposed opposite an actuating mechanism 23, the details of which form no part of the present disclosure, but which includes a pointed striker propelled into the recess 22 at the time of initiation of operation of the device. The recess 22 includes a seat 24 for a frangible disc 25 which is broken upon contact with the actuating mechanism 23. Disposed inwardly of the seat 24 is a generally horizontally disposed passage 26 communicating at the inner end thereof with a vertical passage 27 in the septum 21. The vertical passage 27 also includes a seat 28 which positions an orificed plate 29 having a tiny orifice (not shown) for the passage of a fluid at a relatively low rate. Oppositely disposed with respect to the recess 22 is a ball check valve means 3%, including an orificed plate 31, a ball check 32 urged against the plate 31 by a spring 33. The means 3% communicates with a horizontally disposed passage 34, the inner end of which communicates with a vertically disposed passage 35 to provide a conduit to the first-stage timing element 12.

The first and second end walls 1920 are similar and symmetrical, each including a generally centrally disposed opening 3'6, 37, respectively.

The first-stage timing element 12 includes a chamber 38 containing a relatively fixed plug member 39 supported in splined anchoring relation at the outer periphery thereof, as indicated by reference character 49. The plug member 39 includes a recess 41 lined with a resilient member 42 (of rubber or synthetic resinous material). The member 42 includes an orifice 43 coaxially aligned with an orifice 44 in the plug member 39, and an orifice '45 in the first end wall 19. Extending through the orifices 43-4i5 is a plunger 46 having an end plate 4-7, the upper surface of which contacts a booster spring 48 coaxially arranged therewith, at a first end 49. The second end 50 contacts the inner surface of the member 42, so that the spring 48 resiliently urges the plunger 46 in a downward direction as seen in FIGURE 2. Secured in hermetically sealed relation with respect to the lower surface of the plate 47 is a bellows 51, the lower end 52 of which is scaled to the upper surface of the wall 21 radially outwardly of the vertical passages 27 and 35.

The second-stage timing element 13 is similar to the first-stage timing element 12, including a chamber 55, a plug member 56 having spline-type connecting means 57. The plug member 56 includes a corresponding recess 58, a sealing member 59, and the coaxially aligned orifices 60, 61 and 62 correspond to the orifices 43-45, inclusive. The plunger 63 is oppositely directed, wherein the end plate 64 is disposed above the main body portion thereof, and the booster spring 65 tends to urge the plunger 6-3 upwardly toward the wall 21. The bellows J 66 surrounds an axially disposed bore 67 having a porous plug 68 therein providing limited communication between the bellows 51 and the bellows 66.

The first-stage latch element 14 and second-stage latch element 15 are similar and symmetrical, and may be described together. Each is mounted upon an outwardly extending surface 71 of the respective end wall 19-20, and includes first and second gate unit-s 74 and 75, respectively. The first unit 74 includes a first member 76 selectively dispose-d in a transverse groove 77 at the outer end of a plunger 46-63. The first member 76 is interconnected by a spring 78 to the end surface 71, and by pin means 80 to an end 81 of the bell crank member 82 having a pintle 83 forming an axis of rotation. The opposite end 84 of the bell crank 82 forms a means for engaging one side of an enlargement 85 on the end of a rod 86 which is resiliently urged downwardly as seen in FIGURE 1 to transmit motion upon such downward movement. The second unit 75 includes a corresponding second member 90 and bell crank 91 having an end 92 forming engagement means for the enlargement 85 on an opposite side thereof,

OPERATION Assuming the device to be fully pressurized through the means 30, and the parts in the orientation shown in FIGURES 1 and 2, rupture of the frangible disc 25 allows air disposed within the bellows 51 to flow past the orificed plate 29 and outwardly of the casing element 11. With loss in pressure, the booster spring 48 pushes the plunger 46 downwardly, to a point where the first-stage latch element 14 will be released. As pressure is lost within the first bellows, air flows through the porous plug 68, permitting the plunger 63 to move upwardly to ultimately release the second-stage latch element 15. By adjusting the flow through the plate 29 in relation to the plug 68, it is possible to provide for a greater or smaller lag in release of the first-stage latch element 14 and second-stage latch element 15.

As the plungers 46 and 63 retract, the groove 77 no longer engages the first member 76 and second member 90 which are initially abutted, and as the spring 78 retracts the first member 76, resilient force on the enlargement 85 causes rotation of one or both of the bell cranks to release the same.

It is to be understood that it is not considered that the invention is limited to those specific details illustrated, for obvious modifications will occur to those skilled in the art to which the invention pertains.

What is claimed is:

A two-stage pneumatic timer mechanism comprising: a casing element, said casing element having an interior septum defining first and second chambers; first and second plunger means slidably disposed within said first and second chambers, respectively, portions of which slidably extend outwardly of said casing element; first and second actuating means associated with each of said first and second plunger means respectively; first and second compressible bellows disposed within said first and second chambers respectively, at the inwardly disposed ends of said plunger means; resilient means urging said plunger means to compressing relation against said bellows; first metering means connecting the first bellows exteriorly of said casing element; said means comprising an orificed plate disposed within a passage, second metering means interconnecting the first and second bellows, said second metering comprising a porous plug, frangible means closing the first metering means and check valve means for filling the first bellows through the casing element.

References Cited by the Examiner UNITED STATES PATENTS 1,712,882 5/1929 Gleason 9237 1,715,125 5/1929 Feit 9138 1,994,974 3/1935 Weidmann 91-412 2,144,893 1/1939 Parker 91-411 2,483,239 9/1949 Sharpe 9261 2,845,514 7/1959 Senseney 9237 2,959,007 11/ 1960 Gregory -3948 FOREIGN PATENTS 12,925 1901 Great Britain.

MARK NEWMAN, Primary Examiner. SAMUEL LEVINE, Examiner. 

